Yoshinori Takizawa

Increased Expression of Phosphatidylcholine (16:0/18:1) and (16:0/18:2) in Thyroid Papillary Cancer

A good prognosis can be expected for most, but not all, cases of thyroid papillary cancer. Numerous molecular studies have demonstrated beneficial treatment and prognostic factors in various molecular markers. Whereas most previous reports have focused on genomics and proteomics, few have focused on lipidomics. With the advent of mass spectrometry (MS), it has become possible to identify many types of molecules, and this analytical tool has become critical in the field of omics. Recently, imaging mass spectrometry (IMS) was developed. After a simple pretreatment process, IMS can be used to examine tissue sections on glass slides with location information. Here, we conducted an IMS analysis of seven cases of thyroid papillary cancer by comparison of cancerous with normal tissues, focusing on the distribution of phospholipids. We identified that phosphatidylcholine (16:0/18:1) and (16:0/18:2) and sphingomyelin (d18:0/16:1) are significantly higher in thyroid papillary cancer than in normal thyroid tissue as determined by tandem mass (MS/MS) analysis. These distributional differences may be associated with the biological behavior of thyroid papillary cancer.

Mutation analysis of the MYO7A and CDH23 genes in Japanese patients with Usher syndrome type 1

Usher syndrome (USH) is an autosomal recessive disorder characterized by retinitis pigmentosa and hearing loss. USH type 1 (USH1), the second common type of USH, is frequently caused by MYO7A and CDH23 mutations, accounting for 70–80% of the cases among various ethnicities, including Caucasians, Africans and Asians. However, there have been no reports of mutation analysis for any responsible genes for USH1 in Japanese patients. This study describes the first mutation analysis of MYO7A and CDH23 in Japanese USH1 patients. Five mutations (three in MYO7A and two in CDH23) were identified in four of five unrelated patients. Of these mutations, two were novel. One of them, p.Tyr1942SerfsX23 in CDH23, was a large deletion causing the loss of 3 exons. This is the first large deletion to be found in CDH23. The incidence of the MYO7A and CDH23 mutations in the study population was 80%, which is consistent with previous findings. Therefore, mutation screening for these genes is expected to be a highly sensitive method for diagnosing USH1 among the Japanese.

Specific localization of five phosphatidylcholine species in the cochlea by mass microscopy.

Phosphatidylcholine (PC), a phospholipid, is a basic structural component of cell membranes. PC species exhibit various binding patterns with fatty acids; however, the distributions of PC species have not been studied in the cochlea. In recent years, imaging mass spectrometry has been used as a biomolecular visualization technique in medical and biological sciences. We recently developed a ‘mass microscope’ consisting of a mass spectrometry imager with high spatial resolution equipped with an atmospheric-pressure matrix-assisted laser desorption/ionization and quadrupole ion trap time-of-flight analyzer. In this study, we applied the mass microscope to analyze cochlear tissue sections. The imager allowed visualization of the localization of PC species in each region of the cochlea. The structures of the PC species were determined using tandem mass spectrometry. PC(16:0/18:1) was highly localized in the organ of Corti and the stria vascularis. PC(16:0/18:2) was mainly observed in the spiral ligament. PC(16:0/16:1) was found primarily in the organ of Corti. These distributional differences may be associated with the cellular architecture of these cochlear regions.

Surgical approach for treatment of carcinoma of the anterior wall of the external auditory canal.

Objective Treatment outcomes for carcinomas of the external auditory canal (EAC) were evaluated regarding radiologic and pathologic factors. Study Design Retrospective case review. Setting University hospital. Patients Fifteen patients histologically diagnosed with carcinomas of the EAC. Intervention A radiologic and pathologic analysis was performed on these patients histologically diagnosed with carcinomas of the EAC and treated surgically at our institution. We evaluated the size of focal defects in the anteroinferior (AI) canal wall of the tympanic bone with preoperative computed tomographic (CT) scans. Histopathologic slides for the same patients were evaluated according to the same criteria as the CT scans. Main Outcome Measure Pathologic features and estimated survival rate. Results Preoperative CT scans of 15 temporal bones demonstrated an AI canal wall defect ranging from less than 1 mm to full-thickness destruction. Six of 15 patients had an AI canal wall defect greater than 2 mm on preoperative CT scan. Pathologic findings in these 6 cases showed extension of the tumor through the AI defect into the anterior soft tissues. Information on patients’ survival status was obtained after a median follow-up period of 78.3 months (range, 18–151 mo). Conclusion Preoperative CT can be used to accurately determine the pathologic extent of tumor invasion in carcinomas of the EAC. This diagnostic method facilitates exchange of accurate clinical data in a comparable form and can be used to evaluate the efficacy of existing and proposed treatments for EAC tumors.

Increased phosphatidylcholine (16:0/16:0) in the folliculus lymphaticus of Warthin tumor

Warthin tumor (War-T), the second most common benign salivary gland tumor, consists mainly of neoplastic epithelium and lymphoid stroma. Some proteins and genes thought to be involved in War-T were evaluated by molecular biology and immunology. However, lipids as an important component of many tumor cells have not been well studied in War-T. To elucidate the molecular biology and pathogenesis of War-T, we investigated the visualized distribution of phosphatidylcholines (PCs) by imaging mass spectrometry (IMS). In our IMS analysis of a typical case, 10 signals were significantly different in intensity (p < 0.01) between the War-T and non-tumor (Non-T) regions. Five specific PCs were frequently found in the War-T regions of all of the samples: [PC (16:0/16:0) + K]+ (m/z 772.5), [PC (16:0/20:4) + K]+ (m/z 820.5), [PC (16:0/20:3) + K]+ (m/z 822.5), [PC (18:2/20:4) + K]+ (m/z 844.5), and [PC (18:0/20:5) + K]+ (m/z 846.5). PC (16:0/16:0) was increased specifically in the folliculus lymphaticus of War-T lymphoid stroma, suggesting a different metabolism. Localization of PC (16:0/16:0) might reflect inflammation activity participating in the pathogenesis of War-T. Thus, our IMS analysis revealed the profile of PCs specific to the War-T region. The molecules identified in our study provide important information for further studies of War-T pathogenesis.

Congenital middle ear cholesteatoma: experience from 26 surgical cases.

Objectives: We analyzed the clinical features and surgical techniques used in cases of childhood congenital cholesteatoma of the middle ear. Methods: We studied 26 patients (26 ears) who underwent surgery for congenital cholesteatoma between January 1998 and December 2009, focusing on the location and type of cholesteatoma, the surgical procedures involved, and the results obtained. Patients with prior otologic procedures were excluded. A 4-stage system was used to grade the cholesteatomas. Results: The frequency of posterior-quadrant involvement and open-type cholesteatomas increased in the more advanced stages. Second-look operations were performed in 60% of stage III and 75% of stage IV cases; and residual cholesteatomas were found in 20% of stage III and 75% of stage IV cases. Of the cases evaluated both before and after the operation, 100% of stage I and II cases, 86% of stage III cases, and 50% of stage IV cases showed improvement in hearing function. Conclusions: The staging system is relatively simple, while accurately reflecting clinical results. However, there are many differences between the anterior and posterior types of congenital cholesteatomas in surgical approach and postoperative progression that are not reflected in the classification systems and require further study. In addition, we reviewed the surgical procedures involved in anterior-quadrant cases, and propose a modified surgical procedure.

Survival outcomes after surgical resection of pulmonary metastases of head and neck tumours.

BACKGROUND There is limited information available regarding the benefits and outcomes of resection of pulmonary metastases arising from head and neck cancers. METHODS A retrospective review was performed of 21 patients who underwent resection of pulmonary metastases of primary head and neck malignancies at Hamamatsu University Hospital. Clinical staging, treatment methods, pathological subtype (particularly squamous cell carcinoma), disease-free interval and overall survival were evaluated. RESULTS The 5- and 10-year overall survival rates of the study participants were 67.0 per cent and 55.0 per cent, respectively, as determined by the Kaplan-Meier method. The prognosis for patients with a disease-free interval of less than 24 months was poor compared to those with a disease-free interval of greater than 24 months (p = 0.0234). CONCLUSION Patients with short disease-free intervals, and possibly those who are older than 60 years, should be categorised as having severe disease. However, pulmonary metastases from head and neck malignancies are potentially curable by surgical resection.

Relationship between tympanic membrane retraction and habitual sniffing in patients with cholesteatoma.

Abstract Conclusion: Habitual sniffing affects the pathogenicity and recurrence of cholesteatoma. Postoperative instructions requesting patients to cease sniffing may reduce the retraction and recurrence of cholesteatoma. Objective: To examine the relationship between tympanic membrane retraction and habitual sniffing in patients with cholesteatoma. Methods: We recruited 98 patients (102 ears) who were surgically treated for cholesteatoma by canal wall-down tympanoplasty (22 ears) or canal wall-down tympanoplasty with reconstruction methods (80 ears). We classified these patients into two groups on the basis of their preoperative habitual sniffing: habitual and non-habitual sniffers. The findings of the contralateral tympanic membrane were examined in each group and were classified according to the Tos classifications. Next, we evaluated the incidence of 1-year postoperative tympanic membrane retraction treated by the canal-down tympanoplasty with reconstruction method in the following three groups: non-habitual sniffing group, sniffing cessation group, and continual sniffing group. Results: In habitual sniffers, the Tos classifications of contralateral tympanic membrane were normal in 7% (3/41). In contrast, for non-habitual sniffers, the findings were normal in 39% (21/54). These results indicate that sniffing causes tympanic membrane retraction. The tympanic membranes of patients in the sniffing cessation group were largely normal after surgery. However, more than 50% of the patients who continued to sniff after surgery showed retraction or recurrent cholesteatoma.

Clinical Study of Carcinomas of the External Auditory Canal: Histologic and Treatment Groups

Objectives: Evaluation of the clinical and pathological factors associated with treatment and outcomes for external auditory canal (EAC) carcinomas. Methods: Over the 20-year period from 1993 to 2013, a retrospective review of clinical and pathological analysis was performed on 23 patients who were histologically diagnosed with EAC carcinomas and treated at Hamamatsu University Hospital. We evaluated the clinical staging, treatment methods, pathological diagnosis (particularly squamous cell carcinoma [SCC])), and patient outcomes. Main outcome measures included staging, treatment procedures, pathological features, and estimated survival rates. Results: The 5-year overall survival (OS) of the subjects was 75.2%, and the 10-year OS was 60.2% with the Kaplan-Meier method. The prognosis for SCC was poor when compared with other carcinomas (P = .0462). The prognosis following treatment with surgery alone and following postoperative radiotherapy or chemoradiotherapy was significantly better than for the group of patients with unresectable tumors (P = .0004 and P = .0001). There was no significant difference between the 4 tumor stage groups. Information on patients’ survival status was obtained after a median follow-up period of 57.5 months (range, 7-151 months). Conclusions: Our survival analysis data for carcinoma of the EAC demonstrates that SCC and unresectable cases are associated with poor outcomes, and outcomes for subjects with operability more closely parallel the survival curves of advanced stage T4 disease. Patients with SCC should be strictly categorized as cases with severe disease.

Erratum to: Increased phosphatidylcholine (16:0/16:0) in the folliculus lymphaticus of Warthin tumor

Erratum to: Anal Bioanal Chem DOI 10.1007/s00216-014-7890-9 Fig. 5 Molecular identification by the MS/MS analysis of tissue sections. The precursor ions were m/z 772.5 (a), m/z 820.5 (b), m/z 822.5 (c), m/z 844.5 (d) and m/z 846.5 (e). From the product ion spectrum, a molecule corresponding to m/z 772.5 was identified ... The authors would like to call your attention to the following: The legend of Figure 6 should read “Location of PC (16:0/16:0) in the War-T region. The ion images of m/z 772.5, identified as [PC (16:0/16:0) + K]+, were merged with the HE staining image for case 1. According to the HE staining, we discriminated the neoplastic epithelium and lymphoid stroma on the basis of the description in Fig. 1. The ion image showed that the signal at [PC(16:0/16:0) + K]+ (m/z 772.5) was more intense in the lymphoid stroma and performed clusters in the regions circled by red lines, folliculus lymphaticus”. The sentence “In our study, most of the lipids detected in the War-T regions included two double bonds, such as PC (16:0/18:2)” should read: “In our study, most of the lipids detected in the War-T regions included more than two double bonds, such as PC (16:0/20:3)”. The paragraph under Figure 6 should read: “However the signal at [PC(16:0/16:0) + K]+ (m/z 772.5) showed a different localization compared to the other War-T signals. The merged ion images of [PC(16:0/16:0) + K]+ (m/z 772.5) and [PC(36:2) + K]+ (m/z 824.5) revealed a clear positional discrimination between these two biomolecules. By comparison with the HE staining images, the signal at [PC(36:2) + K]+ (m/z 824.5) was found at neoplastic epithelium. In contrast, the signal at [PC(16:0/16:0) + K] + (m/z 772.5) was located mainly in lymphoid stroma (Fig. 4). Especially, the folliculus lymphaticus in the War-T region exhibited high signal intensities at [PC(16:0/16:0) + K]+ (m/z 772.5)” Unfortunately, there was a mistake in Figure 5 of this contribution. Please find the correct Figure 5 below: